The toes of the human foot are very commonly contracted. The contracture of a toe produces pain due to increased pressure at the plantar metatarsal head, the dorsal proximal interphalangeal joint, and the distal end of the toe. Procedures utilized to correct the deformity include tendon release, tendon transfer, partial joint (interphalangeal joint) resection (arthroplasty), and joint (interphalangeal joint) fusion (arthrodesis). For flexible deformities, tendon procedures are often utilized. With a reducible contracture of a toe, a transfer of the flexor digitorum longus tendon to the extensor tendon apparatus is often used with a variety of techniques. The contracted flexor digitorum longus tendon is released from its insertion on the base of the distal phalanx and it is transferred medial or lateral to the proximal phalanx and sutured to the extensor tendon apparatus dorsally with the tendon tensioned to correct the alignment of the toe. This releases the deforming force of the contracted flexor tendon on the interphalangeal joints while preserving the tendons ability to flex the metatarsophalangeal joint. Correcting the alignment can alleviate the pain associated with the contracture.
Current procedures are performed to facilitate a secure new insertion for the flexor digitorum longus tendon despite the new location being less than ideal. Procedures to transfer the flexor digitorum longus tendon within the toe all have the goal of plantar flexing of the proximal phalanx at the metatarsophalangeal joint while releasing the contracture of the interphalangeal joints. Unfortunately, current procedures do not provide insertion of the flexor digitorum longus tendon to the plantar base of the proximal phalanx where it can best serve its new purpose. With attachment of the transferred flexor digitorum longus tendon to a location other than the plantar base of the proximal phalanx, metatarsophalangeal joint instability can persist, and transverse deviation of the toe can be exacerbated. The tendon is not routinely attached to its ideal new insertion due to technical difficulties and inadequate fixation methods.
Rerouting the flexor digitorum longus tendon through a dorsal to plantar drill hole in the proximal portion of the proximal phalanx is a procedure option, but this creates a large hole subject to fracture. The procedure is also technically difficult.
During a direct repair of a plantar metatarsophalangeal joint capsule (plantar plate) rupture, the flexor digitorum longus tendon is often used to reinforce the repair. The tendon is secured to the plantar base of the proximal phalanx with transosseus suturing or a small tendon anchor. The bone of the proximal phalangeal base is small and using the currently available tendon suture anchors is difficult—especially considering the challenge of appropriately tensioning the tendon while trying to secure it into its new insertion with suture. The aging population and associated osteopenia adds to the difficulty of attaining secure tendon to bone fixation. Other than a direct plantar metatarsophalangeal joint ligament repair type procedure, most efforts to simply realign a contracted toe are from dorsal, so the plantar base of the proximal phalanx is not exposed. If a secure means of fixation for the flexor digitorum longus tendon under appropriate tension for correcting a contracted toe could be done efficiently, and reproducibly, the approach to reconstructing the common deformity could be vastly improved.
It is therefore an object of the present invention to provide retention between a flexor digitorum longus tendon and the plantar aspect of a proximal phalangeal base for the correction of a toe contracture.
It is also an object of the present invention to provide retention between a flexor digitorum brevis tendon and associated foot bone.
It is further an object of the present invention to provide retention between a tendon/ligament and associated bone in various parts of the body.